Effect of therapeutic concentrations of anthracyclines on monocyte phagocytosis of yeast cells.

The effect of therapeutic concentrations of doxorubicin, epirubicin, and mitoxanthrone on mature leukocyte function has been examined by measuring phagocytosis of yeast cells by surface-bound monocytes, using a fluorescence-quenching method. There was a 10% inhibition of monocyte phagocytosis by doxorubicin, but epirubicin and mitoxanthrone had no effect on monocyte phagocytosis. Anthracyclines may have a major immunosuppressive effect due to bone marrow depression. The lack of interference with mature monocyte function by epirubicin and mitoxanthrone provides a potential advantage in comparison with the parent compounds.